If none of the below helps, please report in the comments and include your seed, platform and version, and coordinates.
Common user errors
If your in-game world doesn't match the map here at all, it's most likely due to one of the following:
- you entered the wrong seed or coordinates
- you selected the wrong edition or version (the one used to generate the region you look at)
- you used mods or resource packs that affect world generation
- (for slime chunks) you didn't wait long enough, since they have a very low spawn rate even in slime chunks
Many features are not 100% accurate, i.e., locations can be wrong or missing. These include:
- End Cities on Bedrock Edition
- World Spawn Positions
- Amethyst Geodes (near caves, mineshafts, etc.)
Various other structures such as villages and igloos can sometimes fail to generate in-game as well, but this should happen far less frequently than for the features mentioned above.
Mixed version worlds
If you started your world on an older version, you'll have to switch between the versions in the app. Always select the version that was used to generate the chunks you're looking at.
For technical reasons, you need to know the seed of your world to use Seed Map, unless, of course, you want to find a seed for a new world. If you're playing SSP, the app is able to fetch the seed from your savegame. Alternatively, you can use the /seed command ingame. In SMP, you can use the same command if you have sufficient rights. Otherwise, however, you're dependent on the server owner, who started the world and has access to the savegame and config files.
This app uses some relatively new web technologies. As a result, some features may be disabled for older browsers. I recommend using the latest version of a major browser such as Chrome, Firefox, Edge or Safari.
The first thing you should do is select a seed and version. You can either type it in manually, or you can load it from your savegame. The latter can be done by clicking on "Load from Save..." and selecting your level.dat, or by drag&dropping the level.dat file into your browser window. Level.dat is a small file located in the folder of every Minecraft savegame. You can find the savegames in the saves folder of your Minecraft installation. On Windows you can use %appdata%\.minecraft\saves to get to that folder.
You should also know that a seed is always a number (up to around 20 digits). If you type in anything else (like letters), it will be converted to a number. The app does this the same way Minecraft does, so it's safe to use letters (and other characters) as well.
Dimension and Feature Selection
Below the seed and version, you can also choose the Minecraft dimension that you want to view (Overworld, Nether or End). This, and the version you use, will affect which features can be enabled. To toggle certain features, click on the icons in the features box just above the map.
You can also expand and collapse features box by clicking the arrow on the right side of the box to show the full names of the features, as well as some more options.
Note that some features will only show if you zoomed in enough. This is to keep the app fast and to not flood it with icons. The app will show a warning and all affected features will be highlighted once that happens.
Once you entered all the options you can start using the map. To scroll, use your arrow keys while your mouse cursor points at the map, or move your mouse while holding down the left mouse button. You can use the slider below the map or your mousewheel for zooming. The lower inputs allow you to go to a specific point (e.g., your base) of the map and set a marker there. You can always remove and add the marker by double clicking on the map. The "Save Map" button allows you to save the currently shown map as png image file.
Selecting structure locations
You can click or tap on the icons on the map to see their exact coordinates in the game. For some structures, additional details are shown as well.
When using a touch-enabled device, an extra option for enabling/disabling touchscreen control will appear below the map. With that option enabled, you can drag the map with your finger to navigate, you can pinch to zoom in and out, and you can tap and hold to set a marker on the map. By double tapping on the map, you can quickly enable/disable the functionality as well.